What Is Tall Fescue Grass?

Tall fescue (Festuca arundinacea) is a cool-season grass best suited to U.S. Department of Agriculture plant hardiness zones 4 through 7. Historically used for pastures, tall fescue's versatility and adaptability gave rise to several turf grass forms. Useful in sunny or partially shaded areas, tall fescue excels in the transition zone where warm and cold climates meet. Employing proper cultural practices can help you maintain a lush tall fescue lawn.

Tall fescue is part of a large genus of fescue grasses known for their ability to put out extensive root systems. As a result, the grass tolerates drought conditions when properly established. In normal conditions, tall fescue does not require irrigation unless it wilts or shows signs of water stress. The grass grows in bunches and produces erect, flowering stems known as tillers, if not mown. In pasture situations, tall fescue tillers reach heights of 3 to 4 feet.

One key to success with tall fescue is keeping the grass long even to encourage its deep roots. You can grow tall fescue in parks, lawns and golf courses, as long as you keep the grass above 1 1/2 inches tall. Tall fescue develops weak root systems when cut too short. Recommended mowing heights change depending on the time of year. Spring grass can be kept at 2 to 2 1/2 inches, but grass grown in the summer or in shade should be kept at 3 to 3 1/2 inches or more.

Tall fescue is generally seeded in the cool spring or fall seasons during its strongest period of active growth. Seeding rates for tall fescue range from 6 to 8 pounds of seed per 1,000 square feet. In climates with warm summers, fall seeding is best. Spring-sown tall fescue struggles with summer heat and humidity and becomes more susceptible to heat stress and fungal disease. Keep tall fescue seed moist, but never overly wet, for proper germination and reduced risk of fungal diseases.

Turf grasses often need fertilizers or soil amendments to maintain healthy soil pH and good growth. Tall fescue requires a pH range of 5.8 to 6.5 to access soil nutrients it prefers. A soil test confirms if your lawn needs amendments to alter pH or add nutrients. For example, liming raises pH in acidic soils and sulfur reduces alkalinity. Nitrogen should be applied to tall fescue fall and late spring at a rate of 1 pound of actual nitrogen per 1,000 square feet. Avoid fertilizing tall fescue in the summer or the grass could burn.